The NSW Environment Protection Authority (EPA) has confirmed that Sydney Water’s Malabar Wastewater Treatment System is the likely source of the debris balls that washed ashore along several NSW beaches between October 2024 and February 2025.
The finding follows evidence gathered by Sydney Water under an EPA Preliminary Investigation Notice, which traced the origin of the debris to within the Malabar system. The EPA’s Independent Wastewater Expert Panel reviewed the evidence in September 2025 and recommended that Sydney Water undertake further investigations to identify the exact cause and contributing factors within the system.
Sydney Water has now commenced this work, which will guide short-, medium- and long-term measures to prevent a similar incident in the future. The investigations are expected to be completed by the end of 2025.
The EPA has stated it will continue to oversee the investigation and work with Sydney Water to ensure that corrective actions are implemented and risks to the marine environment are reduced. Updates will be provided to the community as further information becomes available.
